Gas-phase biphenylphenol polymerization catalysts

A method for making a polymer, the method comprising:

• contacting a supported gas-phase biphenylphenol polymerization catalyst with an olefin under polymerization conditions in a gas-phase polymerization reactor to make the polymer via a gas-phase polymerization process, wherein the supported gas-phase biphenylphenol polymerization catalyst is made from a gas-phase biphenylphenol polymerization precatalyst of Formula I:
• wherein each of R5, R7, R8, and R10 is independently is a (C1 to C20) alkyl, aryl, aralkyl, halogen, or a hydrogen;
• wherein each of R4 and R11 independently is a halogen or a hydrogen;
• wherein each of R2 and R13 independently is a (C1 to C20) alkyl, aryl or aralkyl or a hydrogen;
• wherein each of R15 and R16 independently is a 2,7-disubstituted carbazol-9-yl or a 3,6-disubstituted carbazol-9-yl;
• wherein L is a linear C3 or C4 alkylene that forms a 3-carbon bridge or 4-carbon bridge, respectively, between the two oxygen atoms to which L is covalently bonded;
• wherein each of R1, R3, R12, and R14 independently is a (C1-C5) alkyl, halogen, or a hydrogen;
• wherein each of R6 and R9 is a hydrogen or (C1-C8) alkyl;
• wherein each X independently is a halogen, a hydrogen, a (C1-C20) alkyl, a (C7-C20) aralkyl, a (C1-C6) alkyl-substituted (C6-C12) aryl, or a (C1-C6) alkyl-substituted benzyl,—CH2Si (RC) 3, where RC is (C1-C12) hydrocarbon;
• wherein M is Zr or Hf;
• and
• wherein the polymer formed at B-conditions (H2/C2=0.0017 and C6/C2=0.004 at 100° C. and 230 pounds per square inch (psi) ethylene) has a molecular weight (Mw) in a range of from about 150,000 Daltons to about 1,200,000 Daltons;
• or wherein the polymer formed at K-conditions (H2/C2=0.0068 and C6/C2=0.004 at 100° C. and 230 psi) has Mw of less than about 500,000 Daltons.